Results 61 to 70 of about 2,212 (110)

森林涵养水源的价值核算研究

Shuitu Baochi Xuebao, 2003
森林涵养蓄水价值量核算方法较多,包括土壤蓄水估算法、水量平衡核算法、多因子回归法和用地下径流增长法计算森林涵养水源的价值。但此方法存在一个问题,需要分别求出森林涵养水源的价值,然后进行合成。在合成过程中,可能存在信息叠加等问题,使计算结果偏离实际,为此提出了森林涵养水源价值量核算模糊数学模型,V=(A○R).S,A为要素评价的权重值,R为影响森林涵养水源单要素评判矩阵所组成的综合评价矩阵,S为水资源价格向量,S=(P,P1,P2,P3,0)。
姜文来
doaj  

林火干扰下亚热带森林土壤胞外酶化学计量特征

Shuitu Baochi Xuebao
目的森林火灾作为亚热带森林生态系统主要的自然和人为干扰过程，严重影响土壤生物化学循环过程。为明确土壤胞外酶活性计量特征对林火干扰后恢复过程的响应。方法以亚热带次生林林火干扰后不同恢复阶段的土壤为研究对象，采用空间替代时间序列的方法选取7个次生林恢复阶段的亚热带森林土壤，并将其分为老龄林(60~70 a)、中龄林(30~40 a)和幼龄林(＜20 a)，通过测定土壤碳(C)、氮(N)、磷(P)相关的转化酶活性，揭示林火干扰下亚热带森林土壤胞外酶活性及其化学计量特征的演替规律。结果土壤纤维素水解酶(CBH ...
郭琦玲, 王建青, 毛娇艳, 孙嘉雯, 黄雨晴, 施秀珍   +5 more
doaj  

川西高山峡谷区6种森林枯落物的持水与失水特性

Shuitu Baochi Xuebao, 2019
川西高山峡谷区森林较高的地表枯落物储量可能具有较好的水文生态效益，但缺乏研究关注。以川西高山峡谷区6种森林为对象，在雨季调查了不同森林地表枯落物的持水和失水特性。结果表明：（1）川西高山峡谷区林地枯落物蓄积量与最大持水量和有效拦蓄量呈显著正相关，林地枯落物蓄积量为6.90~17.49 t/hm2，最大持水量为1.64~5.42 mm，最大持水率为138.18%~330.09%，有效拦蓄量为0.53~3.33 mm，有效拦蓄率为77.57%~203.02%。（2）相对其他森林，亮叶桦（Betula ...
刘一霖, 温娅檬, 李巧玉, 陈娟, 张小晶, 吴福忠, 杨万勤, 谭波   +7 more
doaj  

[Risk Factors and Prognosis of Pneumoconiosis Combined With Bacterial Pneumonia: Application of a Random Forest Model]. [PDF]

Sichuan Da Xue Xue Bao Yi Xue Ban
Wang Q, Xie L, DU W, Chen M, You R, Jin Q.   +5 more
europepmc   +1 more source

[Prediction of hemorrhage rate after tonsil surgery in children based on random forest model]. [PDF]

Lin Chuang Er Bi Yan Hou Tou Jing Wai Ke Za Zhi
Xu H, Qiu S, Wang J, Han F, Xia Z, Ni L, Ma J, Chen C, Gao X, Zhang J, Liu H, Liu H, Yao H, Zhuang Q, Song W, Zhao S, Zhang M, Liu D, Li X.   +18 more
europepmc   +1 more source

Shinrin-Yoku (Forest Bathing): A Scoping Review of the Global Research on the Effects of Spending Time in Nature. [PDF]

Glob Adv Integr Med Health
Vermeesch AL, Ellsworth-Kopkowski A, Prather JG, Passel C, Rogers HH, Hansen MM.   +5 more
europepmc   +1 more source

Construction of a diagnostic model based on random forest and artificial neural network for peri-implantitis. [PDF]

Hua Xi Kou Qiang Yi Xue Za Zhi
Yang H, Chen Y, Zhao A, Cheng T, Zhou J, Li Z.   +5 more
europepmc   +1 more source

[Development and validation of an interpretable machine learning model for predicting reguirement of early invasive mechanical ventilation in patients with acute pancreatitis]. [PDF]

Nan Fang Yi Ke Da Xue Xue Bao
Wu X, Sha T, Hu H, Sun M, Wu J, Chen Z.
europepmc   +1 more source

[Development of a machine learning-based ionization efficiency prediction model for per- and polyfluoroalkyl substances and its application in semi-quantitative analysis]. [PDF]

Se Pu
Sun SZ, Li YY, Gao Y, Li KC, Chen Z, Li XQ, Zhang QH.   +6 more
europepmc   +1 more source

[A Randomized Controlled Clinical Trial of Acupuncture at the Sphenopalatine Ganglion for the Treatment of Allergic Rhinitis]. [PDF]

Sichuan Da Xue Xue Bao Yi Xue Ban
Huang J, Zhong B, Wang F, Zhang Y, Qiu Y, Wei X, Deng J, Song H.   +7 more
europepmc   +1 more source